首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   68289篇
  免费   2652篇
  国内免费   20篇
  70961篇
  2019年   859篇
  2018年   1117篇
  2017年   1159篇
  2016年   1263篇
  2015年   908篇
  2014年   1088篇
  2013年   5301篇
  2012年   2002篇
  2011年   2202篇
  2010年   1393篇
  2009年   1378篇
  2008年   1978篇
  2007年   1996篇
  2006年   1856篇
  2005年   1650篇
  2004年   1531篇
  2003年   1471篇
  2002年   1570篇
  2001年   2103篇
  2000年   2093篇
  1999年   1601篇
  1998年   833篇
  1997年   741篇
  1996年   744篇
  1995年   667篇
  1993年   662篇
  1992年   1355篇
  1991年   1252篇
  1990年   1217篇
  1989年   1128篇
  1988年   1104篇
  1987年   1071篇
  1986年   1152篇
  1985年   1156篇
  1984年   1000篇
  1983年   934篇
  1982年   707篇
  1981年   697篇
  1979年   1036篇
  1978年   795篇
  1975年   888篇
  1974年   945篇
  1973年   1026篇
  1972年   861篇
  1971年   788篇
  1970年   702篇
  1969年   728篇
  1968年   924篇
  1967年   817篇
  1966年   706篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
951.
This study uses data from adolescents matched with data from their friends to examine whether reference group effects on adolescent sexuality should be thought of as operating through the sharing of norms or the modeling of behavior. We observe that perception of attitudes has such a trivial reality component and such a strong autistic component that it cannot serve as a mechanism of peer influence. Perception of sexual behavior has a reality component which is as large as its autistic component, and large enough to serve as a route of influence. We reach two conclusions: (1) Reference group effects on adolescent sexual behavior probably work through behavior modeling rather than through normative influence. (2) Studies which infer peer influence on sexual behavior using only perception of peers will arrive at erroneous conclusions.  相似文献   
952.
953.
Video games vary in terms of the emotional states they elicit from players. These differences in emotional reactions, in turn, help account for differential preferences of individual games. The three independent dimensions of pleasure-displeasure, arousal-nonarousal, and dominance-submissiveness were used to assess emotional impacts of individual games. In addition, a preference measure was constructed to evaluate attraction toward, versus avoidance of, specific games. In Study One, a group of subjects provided data on emotional responses to 22 common arcade video games and a different group rated their preferences for the same games. The emotional impact of video games was highly unpleasant, moderately arousing, and moderately dominance-inducing; thus, the predominant emotional response to these games was aggression, anger, or hostility. I n Study Two, subjects visiting a video game arcade were recruited and assigned to play two games each and to report their reactions to each game immediately after playing the game. Results showed that greater feelings of pleasure, and separately of arousal, while playing video games resulted in higher preferences for the games and that greater dominance (significant only for males) also led to higher preferences. It may be beneficial, therefore, to experiment with more arousing and more dominance-inducing game designs which are not necessarily unpleasant or which definitely yield high pleasure.  相似文献   
954.
Three students with moderate handicaps were taught to initiate and expand on conversational topics. The teaching procedure used stimuli generated from actual conversations with nonhandicapped peers. Generalization was assessed by audiotaping conversations between the handicapped students and their peers in natural school contexts without adult supervision. Results indicated that training generalized to natural contexts. These results were socially validated by undergraduate special education students, who rated tapes of two of the students' conversations during training phases as more socially competent than during baseline. Results are discussed in terms of the evaluation of complex social behavior as multioperant behaviors.  相似文献   
955.
Superimposition of response-independent reinforcement   总被引:6,自引:6,他引:0       下载免费PDF全文
Studies that have superimposed response-independent reinforcement (or reinforcers scheduled by contingencies placed on the absence of responding) upon conventional response-dependent schedules are reviewed. In general, providing alternative sources of reinforcement reduced response rates below the levels observed when alternative reinforcement was absent. However, response-rate elevation was sometimes found, particularly when rates of superimposed response-independent reinforcement were low. Superimposition of schedules providing reinforcers contingent on the absence of responding usually produced more severe response-rate decrements than superimposition of response-independent reinforcement. A variant of Herrnstein's equation, which assumes that some of the alternative reinforcers function as if they were delivered by baseline response-dependent source of reinforcement, is in qualitative agreement with the overall body of results obtained, and can predict both increases and decreases in response rate as resulting from superimposed reinforcers.  相似文献   
956.
Seven albino rats were exposed to a multiple schedule of reinforcement in which the two components (fixed interval and extinction) alternated such that a presentation of the extinction component followed each fixed-interval reinforcement. In baseline sessions, the duration of the extinction component was constant and always one-third of the fixed-interval value. Probe sessions contained a probe segment in which the duration of the extinction component was increased; the response rate in fixed-interval components during the probe segment was compared with the response rate in the segments preceding and following the probe. The effect of increasing the duration of the extinction component was studied under three values of fixed interval: 30 s, 120 s, and 18 s, in three successive conditions. Response rate within fixed intervals was a direct function of duration of the extinction component. Pausing at the beginning of the fixed interval decreased as extinction duration increased. These effects were larger and more consistent for the shorter fixed-interval values (18 s and 30 s). These results indicate a functional relation between relative component duration and responding. For the component providing more frequent reinforcement, this could be stated as an inverse relationship between relative component duration and response rate. This relation is similar to findings regarding the ratio of trial and intertrial duration in Pavlovian conditioning procedures, and suggests that behavioral contrast may be related to Pavlovian contingencies underlying the multiple schedule.  相似文献   
957.
Three experiments describe the effects of manipulating the frequency of response-reinforcer contiguity in a recycling conjunctive schedule. The schedule arranged that a reinforcer was delivered after 30 s provided at least one response had occurred; otherwise the next cycle started immediately. In Experiment 1, this schedule produced the typical pause–respond–pause pattern, with most responses at mid-interval; and, when a limited number of contiguities between responses and food delivery were added, the pattern became more like the monotonic scallop seen on fixed-interval schedules. In Experiment 2, the schedule was initially presented with an additional contingency that allowed contiguity on every trial. Fixed-interval-like behavior occurred and tended to persist as contiguities were gradually eliminated. In Experiment 3, the recycling conjunctive schedule alternated with a condition in which a large number of contiguities occurred. The pause–respond–pause pattern and fixed-interval-like performance occurred with few or many contiguities, respectively. The results of all three experiments illustrate how contiguity interacts with a small number of other variables to determine performance on interval schedules and illuminate previous findings with fixed-interval and fixed-time schedules.  相似文献   
958.
Belief systems and attitudes toward the death penalty and other punishments   总被引:1,自引:0,他引:1  
This study focused on the relationship of belief systems as a configural construct and conservatism-liberalism to attitudes toward the death penalty and other punishments for offenses of varying severity Extrapersonalists, the most concretely functioning of the four conceptual or belief systems posited by Harvey, Hunt, and Schroder (1961), were most in favor of the death penalty They also endorsed the most severe punishment for a variety of crimes, to a particularly greater extent than did representatives of either of the two more abstractly functioning systems The belief dimensions of Openness, Evaluativeness, and Complexity, as well as the frequency of church attendance, correlated more highly and consistently with attitudes toward punishment than did either Conservatism-Liberalism or gender Both of the latter variables failed to correlate with a number of the outcome variables and related at only low levels to the others The greater predictive power of a configural conception of personality or belief systems over a unidimensional conception seems to have been demonstrated Configural concepts may additionally be generally superior to multidimensional concepts treated linearly  相似文献   
959.
This investigation examines the proposition that wives who describe their personality in ways that deviate from sex stereotypes will become less positive and more negative about their marriage from before to after they become mothers, particularly when the transition to parenthood is accompanied by an increase in the traditionalism of marital roles. Sixty-one couples were studied longitudinally from the last trimester of pregnancy through the third postpartum month. The wives completed the Personal Attributes Questionnaire (Spence & Helmreich, 1978), which measures the extent to which they ascribe personality attributes stereotyped as "masculine" (i.e., instrumental, agentic) and "feminine" (expressive, affectional) to themselves, and several questionnaires assessing the marital relationship at both times of measurement. Results revealed that the more division of labor changed toward traditionalism, the greater the decline in wives' evaluations of the positive aspects of marriage and that changes in wives' evaluations of both positive and negative aspects of marriage can be significantly predicted by the interaction of the wives' expressivity and changes toward increased traditionalism in division of labor. Additional analyses showed that wives who do not ascribe female sex-typed attributes to themselves (relative to those who see themselves in sex-stereotyped ways) are more apt to evaluate their marriage less favorably from before to after parenthood when roles shift toward greater traditionalism.  相似文献   
960.
Traditional behavioral genetic methods involve the use primarily of family, twin, and adoption correlations to estimate the relative contributions of genetic and environmental influences in the etiology of individual differences. These methods and representative results for personality are described. However, newer methods are emphasized: structural models and model-fitting, multivariate analysis, genetic change and continuity in development, shared and non-shared components of environmental variance, and genetic components of "environmental" variation. Because most applications of these behavioral genetic methods to the study of personality involve self-report omnibus questionnaires, an important direction for future research in this area is to use these methods to explore new issues and new measures that have emerged from personality theory and research during the past decade.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号